Automatic telephone switch



April 2z 1924.' 1,491,351 J. L. MCQUARRIE AUTOMATIC TELEPHONE SWITCHFiled DeG- 15. 1920 ffy 2.

Patented Apr. 22, 1924.`

[,UNITED STATES PATENT OFFICE.

JAMES L. MCQUARRIE, OF NEW YORK, N. Y., ASSIGNOR TO WESTERN ELECTRICCOM- PANY, INCORPORATED, OF. NEW YORK, N. Y., A CORPORATION F NEW YORK.

AUTOMATIC TELEPHONE SWITCH.

Application filled December 15, 1920'. Serial No. 430,896.

To all ywhom t may concern: y

Be it known that I, JAMES L. MCQUARRTE,

' a citizen of the UnitedStates, residing at New York, inthe county ofNew York, State of New York, have invented certain new and usefulImprovements in Automatic Telephone Switches, of which the following isa full, clear, concise, and exact description.

This invention, relates to automatic switches, and more particularly, toautomatic switches of the type yused in telephone exchanges.

n The invention is an im rovement upon ap- "plicants U. S. Patent Nb.1,290,616, issued January 7, 1919.r

. lIt is the ob `ect of this invention to provide a switch of thetypedescribed in the above mentioned patent, which will serve a largernumber .of trunks or subscribers lines with- .out materially increasingthe size of the structure. l

A feature ofthe present invention is the use .of a contact bank of thepanel t'pe in connection with a switch of the wellnowny up and aroundstructure. having arcuate rows of contacts on both sides, but situatedin different sectors, soA that a rotary sweep of the contact brushesfirst wipes over the conta-cts on one side of the bank and then over thecontacts on the other side. This arrangement doubles the number of linesavailable at one sweep of the contact brushes i without increasing thewidth of the banks and only slightly increasing the thickness.

With reference to the accompanying drawing, Fig. 1 is a plan View of oneend of an automatic switch and Fig. 2 is an elevation, partly insection, showing a part of the switch. suflicient to illustrate theinvenf tion. f

As in the switch described in U. S. Patent No. 1,290,616, lpreviouslyreferred to, the present invention is shown embodied in a switchstructure ycomprising two bank roups, each consisting of a plurality ofunitayers 1, between which are situated a number of rotatable andlongitudinally movable 'brush rods 2. On each brush rod there is mountedtwo sets of contact brushes 7 and 8 respectively. The two setsof brushesare connected in multiple and are therefore electrically equivalent to asingle set. One brush rod and its brushes are shown in the drawing, butit will be understood that there would ,ordinarily be several brushrods, situated at intervals between the bank groups.

The unit layers 1 of thetwo bank groups may be vertically staggered withrespect 'to each other, as illustrated, or, if desired, the unit layersin the two groups may be on the same levels, that is, not staggered.Each lunit layer comprises a plurality of longitudinally `extendingmultiple conductors 3, each separated from the others by insulatingstrips 4. The conductors 3 are situated on both sidesof the unit layers,that is, top and bottom, and. those on the top Vare separated from thoseon the bottom by the insulating strips 5.

At each brush position, each unit layer is provided with two arcuaterows of contacts 6, one row on the top and the other on the bottom, thelatter being shown in dotted lines in Fig. 1. `There is a contact 6, ateach brush position, for each conductor 3. The twol arcuate rows aresituated in adjoining sectors and each extends through an arc of nearly90.

To select a unit layer, the brush shaft together with brush sets 7 and 8are moved 'vertically tothe desired level, the brushes being situatedduring that moven'ient as shown in Fig. 1.

The brush shaft 2 is then rotated one way or the other, depending uponthe unit layer selected and the brush set 7 sweeps over and makescontact with the row of contacts on the upper side of the selected unitlayer. It' the desired set of terminals does not happen to be in theupper row, the brush shaft con-- tinues its rotation and the brush set 8wipes over the lower row of contacts until the desired set is foundwhereupon the brush shaft stops.

The brushes shown iu dotted lines in Fig. 2 are situated in line with aunit layer on thc far side of the view, which is one vertical step lowerthan the position occupied by the brushes shown in full lines.

The mechanism for operating the switch may be the same as that describedin connection with the aforementioned U. S. Patent No. 1,290,616.

Practical consideration makes it desirable i scribers` lines to beaccommodated. the width of the unit layers is reduced by substantiallyone-halt ot that which would be required it the contact terminals 6 weresituated on only one sidel ot the unity layer.

It has been mentioned in a previous paragraph that each unit. layer lcomprises a plurality oli longitudinally extending multiple conductors 3each separated from the other by insulating' strips 4. The necessity`.tor these multiple conductors 3 prevents the contacts (5 fromoccupying the entire upper tace ot' a unit layer since thecharacteristics of this switch require that the contacts be set inarcuate rows, and in order to occupy the entire upper tace ot a unitlayer the contacts would have to cover an arcuate path ot' 180. It isapparent that such an arrangement oit' contacts would not be practicalas the contacts situated in one halt of the 180 span would interferewith the multiple conductors 3 interconnecting an adjacent bank otcontacts and the contacts in the other halt of the span.

F rom the toregoing, the desirability ot placing` the contacts on bothsides oitl a unit layer, in 90 spans, is readily discernible.

lVhat is claimed is:

l. In an automatic switch, a terminal bank comprising a pluralityv otarcuate rows of contacts, all of said rows situated about a commoncenter and each row in a ditl'erent plane and ditferent sector from theothers.

2. In an automatic switch, a terminal bank comprising two arcuate rowsotl contacts, both of said rows situated about a common center, each rowin a ditterent plane and diierent sector from the others.

3. In an auton'latic switch a terminal bank comprising a plurality otarcuatt` rows of contacts. all ot' said rows situated about a commoncenter, each row in a different plane and dilferent sector troni theothers and al plurality ot sets ot contact brushes` one for the contactsin cach plane, said brushes adapted to be rotated simultaneously oversaid bank contacts, each set ot' brushes engaging the contacts in eachrespective plane during said rotation.

4. In' an automatic switch, a [lat terminal bank, contacts on both sidesof said bank arranged in the same arc, the contacts on one side oi saidbank situated in one sector and the contacts on the other side ot saidbank situated in another sector and two sets oit rotatable` contactbrushes, one of said sets o'l" brushes adapted to engage the contacts onone side ot' said bank and the other set of brushes adapted to engagethe contacts on the other side of said bank.

5. In an automatic switch. a fiat terminal bank, contacts on both sidesotl said bank arranged in the same arc., t-he contacts on one side ofsaid bank situated in one sector and the contacts on the other side ofsaid bank situated in another sector, and a 'single operating memberhaving two sets of rotatable contact brushes thereon, one of said setsof brushes adapted to engage the contacts on one side of said bank andthe other set of brushes adapted to engage the contacts on the otherside of said bank.

In witness whereof, I hereunto subscribe my name this 14th day ofDecember A. D.,

JAMES L. MCQUARRIE.

